How would it feel to go down in history as Alfonso the Slobberer, Ivar the Boneless, or Justinian the Slitnosed? Back when surnames weren't universal, nicknames were the way to distinguish this Henry from the other Henry you knew, and those nicknames were even more important when kings and warlords inherited both realms and given names from their predecessors. Medievalists.net compiled a list of the worst names for medieval rulers they've found, with the stories behind each. For example, take Henry the Impotent:

Henry IV of Castile ruled the Spanish kingdom from 1454 to 1474, but he got to the throne he he was known for a royal scandal. When he was fifteen, Henry was married to Blanche II of Navarre. Thirteen years later, Henry sought a divorce, stating that they had never consummated the marriage. The Catholic church held a trial, where they confirmed Blanche’s virginity and received testimony from several prostitutes who explained that Henry’s sexual prowess was just fine, except when it came to his wife. The divorce was granted, and Henry married his cousin Joan of Portugal – she bore him one daughter (although later on his subjects had their doubts on whether he was the father) and then Joan spent most of her time having affairs with various lovers.